Sewing-machine gear-lubricating system



3 Sheets-Sheet l C. A. vKESSLER Filed July 9, 1957 SEWING -MACHINE GEAR-LUBRIGATING SYSTEM July 30, 1940.

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.'5 Sheets-Sheet 2 harZeQ 'ssler July 30, 1940. QA. ,'Kl-:ssLER SEWING-MACHINE GAR-LUBRICATING SYSTEM Filed July 9. 1937 July 30, 1940. c. A.vKEss1.|-:R

SEWING-MACHINE GER-LUBRICATING SYSTEM .Filed July 9, 1957 vC5 'Sheets-Sheet 5 GMM/114A,

Patented July 30, 1940 UNITED STATESv PATENT ori-ice SEWING-MACHINE GEAR-LUBRICATING SYSTEM Charles A. Kessler, Plainfield, N. J. assigner 'to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application July 9, 1937, seriaiN-dj 152,722 w 3 claims. (ci. isa-ef This invention relates to sewing machines having gear-connected top and bottom shafts; a machine of the type in question being disclosed for example, in United States patent of Philip 5:1 Diehl, Re. 16,119, reissued July 21, 1925.

It has been discovered that the chief cause of gear-failure in machines of the type disclosed in said Diehl patent, when driven at speeds above .4000 stitches per minute, is lack of adequate lu- 1U? brication and an object of the invention is to provide a system to adequately lubricate the top and bottom pairsof gears of the machine, which system is so contrived thatA it may be readily installed in aconventional sewing machine in the m field, in substitution for the conventional gear cases thereof, without the necessity of performing any machining operations, such as drilling, tapping, milling, etc.

A furtherobject of the invention is to provide Il a gear-lubricating system which lubricates both the top and bottom pairs of gears of the machine by radially flooding one gear of each pair.

Still further, the invention has for an object to radially flood both pairs of gears from a single pump-cylinder.

It is also an object of the invention to provide for the lubrication of the adjacent bearing bushings of the several shafts, as well as certain adjacent working parts of the sewing machine feeding mechanism.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations, and arrangements of parts hereinafter set forth and illustrated in the l5 accompanying drawings of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

.40 In the accompanying drawings, Fig. 1 is a side elevation, partly in section, of a sewing machine embodying the invention. Fig. 2 is a fragmentary transverse vertical section through the machine when canted rearwardly on the usual table sup- 45 port for'access to the'underbed mechanism. Fig. 3 is a section on the line 3--3, Fig. 1. Fig. 4 is a horizontal section through the upper gear-case axially of the top shaft. Fig. 5 is a horizontal section through the top gear-case at the level of 5() the fastening screw which holds the two sections of the gear-case together. Fig. 6 is a vertical section on an enlarged scale through the oil-pump in the lower gear-case. Fig. 7 is a section on the line 1 1, Fig. 1. Fig. 8 is a bottom end view of the 55 pump-cylinder shown in Fig. 6. Figs'. 9 and 10 are disassembled perspective views of the top and bottom gear-cases, respectively, and Fig. 11 is a perspective-,view of the pump-cylinder.

The sewing machine is constructed with a frameincluding. a bed I, from which-rises the 5, standard 2 of the-gooseneck 3 terminating in the head 4 in which the needle-bar 5 carrying the needle Iiv is journaled to reciprocate. The head 4 also carriesthe usual take-up l, tension device 8 and presser-mechanism, including the presser- 10. foot 9.. The needle-bar 5 and take-up 'l are driven by the usual connections with the top or main shaft I which is journaled in the alined bearing bushings Il, I2, I3, fitted in the gooseneck.

The bottom shaft I4 carries the rotary hook 15. deviceV I which is'complemental to the needle B in the formation of stitches. This bottom shaft I4 is journaledin the bearing bushings I6, I1 tted in the bed'l and is driven from the top shaft lll througlithe tubular upright shaft I8 20 which is journaled in the bearing bushings I9, fitted in the standard 2.

The top shaft I0 has fixed to it a bevel gear 2! which meshes with a bevel gear 22 xedto the open-topped end of the upright tubular shaft I8. 25 The bottom shaft I4 carries a bevel gear 23 which meshes with the bevel gear 24 xed to the upright tubular shaft I8. n

The top-shaft IU carries the usual work-feeding eccentrics 25, 26, which actuate the usual pitman connections 21, 2'8 for the underbed feed rockshafts (not shown). The present workfeedingmechanism is substantially the same as that disclosed in said Diehl reissued patent.

Number 29 represents the usual feed-adjusting 35 lever which is fulcrumed on the stud-screw 30 and is connected by the anchor link 3l to the feed-advancepitman 21, all as more fully disclosed in said Diehl reissued patent.

The top pair of gears 2|, 22 are enclosed by a 40 verticallyrsplit gear-case the sections 32, 33 of which are clamped together by the single fastening screw 34 and grip the reduced inner end 35 of the top shaft bushing I3 as well as the upper end of the upright shaft bushing I9. The gearcase sections 32, 33 are also formed with the registering semi-circular openings 36 which snugly but freely engage the top-shaft I0. The front section 33 ofthe top gear-case carries a wicklled tube'3'l which conducts oil from said gear- A50 case to the fed-eccentrics 25, 26. The rear sec-` tion 32 of said gear-case carries a wick-filled tube 38 which conducts oil to the feed-regulating an- Chor-link 3l. The bearing bushings I3 and I9 are also lubricated from the top gear-case by means of the wicks 39, running lengthwise of such bushings and each exposed at one end to oil within the top gear-case.

The rear section 32 of the top gear-case has a short oil-return pipe-section 4I connected to its bottom wall. 'I'his pipe-section telescopically enters the upper end of the long oil-return pipesection 42 carried by and passing through the top wall of the top section 43 of the horizontally split bottom gear-case 43, 44 which encloses the bottom gears 23, 24. 'Ihe sections of the bottom gear-case are clamped together about and grip one end of the bottom shaft bushing I1. The upper section 43 of the bottom gear-case has an aperture 45 which snugly fits the lowervend of the shaft bushing 20.

The bottom-section 44 of the lower gear-case constitutes an oil-sump and has formed internally on its bottom wall two spaced ledges 46, 46 upon which rest the flange 41 of the pump-cylinderl 48 having near its upper enda lateral oildischarge port 49 in position to direct oil onto the face of the lower bevel-gear 23 within the circle of teeth of such gear, so that the oil will be radially thrownin a sheet by centrifugal force onto the teeth of such gear and thus thoroughly lubricate the bottom gears 23, 24.

The flange 41 of the pump-cylinder 48 is formed with parallel faces 50, 50 which fit freely between the ledges 46 and key the pump-cylinder 48 to the bottom gear-case section 44. By spacing the faces 50, 50 different distances from the axis of the pump-cylinder and shaft I8, it is impossible to assemble the pump-cylinder 48 in the casing 44 in any other position except that shown with the outlet port 49 directed toward the gear 23.

The lower end of the tubular upright shaft I8, which ts in but turns relative to the pumpcylinder 48 is preferably formed with two separate spiral oil-pumping grooves 5I, 52, Fig. 6. The longer groove 5I pumps oil to the outlet port 49 while the shorter groove 52 pumps oil to the port 53 leading to the internal duct 54 extending up within the shaft I8 and through the open upper end of such shaft where the oil is delivered to the gear 22 within the circle of teeth of such gear and is thrown by centrifugal force in the form of a sheet onto the gear teeth. The extreme lower end of the upright shaft I8 is preferably closed, as shown in Fig. 6.

Screwed into the apertured front wall of the bottom section 44 of the lower gear-case is the head 55 of a gage-stick 56 by Vwhich the oillevel 0 may be tested when the machine is canted rearwardly on the table 51, as shown in Fig. 2. Oil may be introduced into the lower gear-case through the gage-stick-receiving aperture to maintain the proper oil-level.

The bearing bushings I1, 20 arelubricated by wicks 58, 59 which pick up oil from the bottom gear-case 43, 44. The upright shaft I8 and lower shaft I4 are formed within the respective bushings I9 and lI1 with spiral grooves 60, 6I which carry the` bearing oil toward and into the respective gear-cases and prevent` oil-leakage from the ends of the bushings remote from the respective gear-cases. I

The gear-cases are preferably die-cast from any suitable material and are practically oiltight when tted to the machine. They may be installed in conventional sewing machines, in

lieu of the grease lled gear-cases heretofore used, without the necessity of performing any special machining operations on the sewing machine frame. All that is required, in addition to a set of present gear-cases, is to provide special bottom and upright shafts and a set of wicklubrcated bearing bushings to be exchanged for the like parts of the conventional machine of the Diehl reissued patent.

It will be understood that when the machine is operated, the double grooved oil pump will pick up oil from the sump and flood the top and bottom pairs of gear therewith by introducing the oil to the body of one of each of said pairs of gears, within the circle of the teeth thereof, whereby the oil willv be thrown by centrifugal force radially of the gears onto the teeth thereof.

The wicks of the tubes 31 and 38 which lubricate the feed-connections do not pick up oil except when the machine is running, at which time oil is thrown onto the ends of the wicks exposed within the top gear-case. None of the remaining wicks receive oil except when the machine is running. When lthe machine is stationary all of the oil inthe system gravitates to the sump in the lower gear-case section 44.

Having thus set forth the nature of the invention, what I claim herein is:

1. In a sewing machine, the combination with top and bottom pairs 'of bevel gears, and top and bottom gear-cases therefor, of means to lubricate said gears including a tubular upright shaft having a duct and carrying one of each of said pairs of bevel gears and formed at its lower end below the bottom gear carried thereby with a spiral oil-pumping groove connected with the duct of said tubular shaft, a floating pumpcylinder embracing the spirally grooved portion of said shaft, a loose key-connection between said pump-cylinder and the bottom wall of said bottom gear-case restraining rotation of the pump-cylinder, and an oil-return pipe connecting the top and bottom gear-cases.

2. In a sewing machine, the combination with top and bottom pairs of gears, and top and bottom gear-cases therefor, of means to lubricate said gears including a tubular upright shaft carrying one of each of said pairs of gears and formed at its lower end with two separate oilpumping spiral grooves one of which is longer than the other, said tubular shaft having a duct opening through the upper end of said shaft and a port connecting the upper end of the shorter spiral groove with the shaft duct, a pumpcylinder embracing the spirally grooved portion of said shaft and formed with a lateral outlet port for oil pumped by the longer of said spiral grooves, said outlet port being positioned to direct oil to one of the lower pairs of gears, and means to return oil from the upper to the lower geartis cases, the wicks of said bearing bushings being 

